Fig. 1

The schematic diagram for the possible transition between the defined state for both the viral load and the CD4 cell counts models [State 1(VL < 50or CD4 ≥ 500), State 2(50 ≤ VL < 1000 or 350 ≤ CD4 < 500), State 3(VL ≥ 1000 or CD4 < 350), State 4 (dead) and State 5 (Loss to follow-up (LTFU)]